One image forming apparatus forms images on a recording medium by transferring a toner image onto the recording medium. Such one conventional image forming apparatus is provided with a waste toner container that accommodates waste toner therein, and a conveying screw disposed within the waste toner container.
The conveying screw includes a rotational shaft and a blade. The rotational shaft is rotatably supported to a pair of side walls of the waste toner container, and the blade is provided on and around the rotational shaft in a spiral manner. The rotational shaft has an end protruding from one side wall, and another end connected to a drive source. There is disposed a coil spring between the other side wall of the waste toner container and the blade. The coil spring is compressed and biases the blade of the conveying screw toward the one side wall.
In such one image forming apparatus, when the conveying screw rotates about the rotational shaft upon receipt of driving force from the drive source, waste toner is conveyed from one side to the other side within the waste toner container. If the conveying screw of the rotational shaft is broken, the end of the rotational shaft is pushed further outward from the one side wall of the waste toner container, due to the resilient force of the coil spring. The rotational motion of the rotational shaft is detected by a sensor, thereby enabling the conveying screw to be detected as being damaged.
Another image forming apparatus forms images on a recording medium by transferring a toner image onto the recording medium. Such another conventional image forming apparatus is provided with a waste toner container that accommodates waste toner therein, a moving member that moves in accordance with the accumulation of the waste toner within the waste toner container, a detection unit that outputs detection results corresponding to the motion of the moving member, and a determination unit that determines whether or not the waste toner has accumulated up to a prescribed accumulation level based on the detection results.
The detection unit includes a light emitting section and a light receiving section disposed in separation from and in opposition to the light emitting section. The detection unit detects whether or not a light path formed between the light emitting section and the light receiving section is blocked. The detection unit is provided at a position outside of the waste toner container.
The moving member includes a connection section, a receiving section and a shielding section. The connection section has a rod-like shape, extending in a horizontal direction. The connection section is pivotably supported within the waste toner container. The connection section has one end protruding outside from the waste toner container. The receiving section has a plate shape and protrudes downward from the connection section within the waste toner container. The shielding section is connected to the one end of the connection section outside of the waste toner container. The shielding section is configured to pivotally move integrally with the receiving section within the waste toner container, thereby either blocking or releasing the light path.
In this another image forming apparatus, in accordance with the increase in the accumulation of the waste toner, the receiving section is pushed upward so that an inclination angle of the receiving section relative to a vertical direction can increase. Accordingly, the shielding section also pivotally moves via the connection section, moving from a position to block the light path to a position to release the same. As a response, the detection unit detects that the light path is now not blocked, based on which the determination unit determines that the waste toner has accumulated up to the prescribed accumulation level within the waste toner container.